The option to use only the halos as DRL's has to do with the light module in the cars.. In version 2 that is used up until sometime in 2007 does not have the possibillity to use only the haloes. After that it is possible.
I haven't seen any coding option for the light module version 2 that allows you to only use them. If one of you guys knows the options for it, please let me know.

If I fit LCI halogens, can my car be coded to use the angel eyes as DRL?

How does this interface with auto lights too? E.g. With my lights on auto, and DRL on, will I get angel eyes all the time, and then main lights when auto kicks in? Or would I need to switch to activating my lights manually?

Ideally I want angel eyes to always be on, and auto lights to function as normal.

Mine is a 2006 E91 with xenon, aut curbe(?) light and high-beam assistant.
I have the FRM2 module and I cannot code mine to only use halo's as DRL. Low beams are always on with that combination.
As I understand it FRM3 can do it. FRM2 and older cannot. Correct me if i'm wrong.